حسین رعنایی

In this study, structural and magnetic evolution of Fe49Co21Mn10Ti10B10 alloy, during mechanical alloying (MA) process, have been investigated by using, X-ray diffraction (XRD), scanning electron microscopy (SEM), electron dispersive X-ray spectroscopy (EDX) and vibrating sample magnetometer (VSM). Structural analyses show that, the Fe-Co based solid solution with BCC Phase Structure of the initial powder mixture occurs at 35 h milling time. It is observed that at 35 milling time, the crystallite size and lattice strain reaches to about 21.50 nm and 0.42 %. The powders exhibited a minimum lattice parameter of ~ 0.28607 nm and maximum volume fraction of grain boundary of 4.35 % after 5 h and 35 h, respectively. Grain size refinement enhances magnetization saturation to about 113.19 emu/g and coercivity to approximately 189 Oe for milling time 5 and 100 h, respectively. Heat treatment of the samples milled at 35 and 100 h demonstrated the crystalline constituent elements and also Fe3O4, MnO2 and TiO crystalline phases. In addition, heat treatment at 600 ?C and 900 ?C for milling times 35 and 100 h led to increase in saturation magnetization and decrease in coercivity. Furthermore, thermal treatment resulted in increasing of crystallite size and decreasing of lattice strains.